A globally comprehensive and accurate map of trail networks does not exist as no mapping organization has a globally comprehensive and accurate routable trail network system. Trails are often on dirt or otherwise unpaved terrain, which also makes the automated mapping (e.g., via car) of trails difficult. What is more, because trails are dirt-based paths, their shapes may change over time (e.g., due to the weather and/or wear), which further complicates the mapping of them.